24bit vs 16bit, the myth exploded!

[U2Bono269]

 
What codec? What bitrate? Did you make the compressed files yourself or did you compare a CD to an iTunes download? Did you line level match? Did you have direct A/B switching? Did you compare the samples blind? You have to test carefully to get accurate results.

I did it using the Foobar plugin with a redbook file I compressed myself at 320kbps, as suggested by the other user.

 

[bigshot]

320 LAME or Fraunhofer?

 

[U2Bono269]

  If you get the 16 and 24 from two different sources, you can't be sure the mastering is the same. That's why you make the 16 from the 24 yourself to test. You want to remove irrelevant variables and focus on what you are testing for. If you are testing just for the difference between 16 and 24 bit, you just want to test for that and not have other factors muddy the waters.

 
Making the files to test myself isn't what I'm curious about. I'm curious about the mastering between the 2 formats. I'm curious about the factors that muddy the waters. Because if I have a CD version, and there's an HD version that does sound different because of the mastering, despite the fact that they are similar sources, I'd be interested in hearing that too. I am interested in the variables. Is that crazy?

 

[U2Bono269]

  320 LAME or Fraunhofer?

 
LAME. But this is getting away from what I'd like to learn more about.

 

[bigshot]

Not at all... Unfortunately, just because it's on HD tracks, it doesn't mean that it is improved. It could be worse than a CD release. It's different with every record, so you have to ask other record collectors who have heard the various masterings which is the best.

 

[RRod]

   
I get that, which brings me back to my original (hypothetical) question...is it possible for a 24bit version of the same release, as in my Achtung Baby example, to sound different for any reason? If the comparison is not made from the same source/format file, is the sound different? Based on your answer above, it seems possible? Has anyone explicitly tested this??

 
Of course it can, if the HD site in question purposefully releases a different master for the 16bit version. I have heard of, for instance, SACDs where the mastering differed between the SACD and Redbook layer, beyond what a simple DSD->PCM conversion would yield; see here for some possible examples.

 

[U2Bono269]

   
Of course it can, if the HD site in question purposefully releases a different master for the 16bit version. I have heard of, for instance, SACDs where the mastering differed between the SACD and Redbook layer, beyond what a simple DSD->PCM conversion would yield; see here for some possible examples.

What if the master is the same, and one file comes from the SACD layer, and the other comes from the CD layer...will they sound the same either in theory or in practice?
 
And to go further, if the master is the same on a separate CD and a separate SACD, will they sound the same in theory or in practice?

 

[RRod]

 
What if the master is the same, and one file comes from the SACD layer, and the other comes from the CD layer...will they sound the same either in theory or in practice?
 
And to go further, if the master is the same on a separate CD and a separate SACD, will they sound the same in theory or in practice?

 
Well note that you can't really master in DSD; you have to convert to PCM to be able to do any of the typical digital manipulations. But we still fall back into the format wars, as SACD proponents would say that the second you go to PCM you lose some special "magic" of DSD. In practice, if all you did was convert the DSD to Redbook competently, you couldn't hear a difference in blind testing.

 

[U2Bono269]

   
Well note that you can't really master in DSD; you have to convert to PCM to be able to do any of the typical digital manipulations. But we still fall back into the format wars, as SACD proponents would say that the second you go to PCM you lose some special "magic" of DSD. In practice, if all you did was convert the DSD to Redbook competently, you couldn't hear a difference in blind testing.

Thank you. Has anyone done an ABX in this sort of scenario?

 

[RRod]

 
Thank you. Has anyone done an ABX in this sort of scenario?

 
Well this is the common reference, but it has its own critics (as you might imagine).

 

[bigshot]

  What if the master is the same, and one file comes from the SACD layer, and the other comes from the CD layer...will they sound the same either in theory or in practice?

 
In practice, the only SACDs I have that have identical mastering on both layers are by PentaTone. Most SACDs have deliberately hobbled redbook layers. This is particularly true of rock legacy titles. I've found that about a quarter of the SACDs I've bought sound better (usually because of a good 5.1 mix), a quarter sound worse, and half of them sound exactly the same as the CD. Not a very good batting average. No surprise the format is dying.

 

[dprimary]

   
I don't agree with that.  There s plenty of science on this thread that shows modern MP3 320 or AAC 256 the differences to lossless are inaudible so no need to remaster anything due to format.  The reason they are doing this push to remaster is to optimize for typical listening conditions of iTunes users (which I have to assume is mobile earbuds).  Which sucks if you are not typical.
 
It would be nice if they start releasing with multiple masters for different conditions, put it as parameters in the EQ.

When you release an album you create a production master for every format you have at some point. Of course for a downloadable format the file is the end of it. Put a copy on the server and you are done. Amazon for example seems to be MP3 256 pretty good but audible. AAC 256 for many things is inaudible for others you can tell but is not easy. None of is night and day like some claim.
 
So you start out with a stereo 24/44.1 mix master (I will leave out higher sample rates to keep it simpler) the mastering engineer will edit and clean up the beginning and end of each track, put the tracks in order of the album adjust the spacing of each track, some tracks might crossfade. Then each track is adjusted for level, eq, dynamic range, possible noise removal. If you intending it to be listens to as an album time between tracks and levels are more important for it to flow as intended. The peak is brought up to just below 0 dBfs this likely took at least a day and a few thousand dollars of time. This is the final master. It will sound as good as it possibly can. Often the producer, engineer and artists  are there for the whole process. 
 
From this 24bit 44.1 master you will create production masters
 
Production masters that require no additional adjustments.
 
WAV 24/44.1
AIFF 24/44.1
FLAC 24/44.1
ALAC 24.44.1
 
These are pretty much a straight forward conversion, still you don't want to sell 10,000 defective FLAC files before anyone catches it. So these are converted and checked for problems.
 
The CD will need to to dithered down to 16bit and have track pointers and such added to it to make a rebook master which will be sent to the pressing plant.
 
Production masters that can require additional adjustment.
 
From the final master or 16 bit master depending on the encoder
 
MP3 128
MP3 256
MP3 320
 
AAC 128
AAC 256
AAC 320
 
Ringtones
 
 
Production masters that require additional adjustments.
 
LP's
12" singles
7" single
 
each will require a lacquer to be cut, each is processed differently.
 
And the lowly cassette
 
With singles on a ten song album you already have 33 production masters. More if you count each downloadable track as an individual master
 
I was told a recent pop album had over 500 masters. I have to feel sorry who ever had to do that.

 

[Greenears]

   
Because I stated in a previous post that I have done ABX testing between mp3s and FLACs, yet multiple posters keep suggesting I do it as if I never said it to begin with...

Great! So I guess you came to the same conclusion everyone else has:  MP3-320 LAME encoded will fail an ABX against lossless.
 
So what were we arguing about again?

 

[U2Bono269]

Listen, I came here to learn and discuss. I don't appreciate the attitude. To my ears lossless sounds better. That's what matters to me so please stop bugging me about it.




Sent from my iPad using Tapatalk

 

[Greenears]

Sounds like you failed the ABX and refuse to believe the writing in the log file.  You just don't want to say it that way.   Welcome to the club.